If you compiled a roster of world-class athletes with asthma, the list would be long — and impressive. From marathon world record holder Paula Radcliffe, to former NBA stars Dennis Rodman and Dominique Wilkins, to tennis star Mary Joe Fernandez and Olympian Jackie Joyner-Kersee, asthmatics have set records and won medals in nearly every sport imaginable.

"I never thought of asthma as an obstacle," said retired swimmer Amy Van Dyken, the first American woman to win four gold medals in one Olympic Games (1996). Her 2000 Olympic teammate Misty Hyman, also an asthmatic, said that throughout her career, asthma was simply something to overcome — another training variable.

Approximately 7 million people ages 18 and under in the U.S. suffer from asthma, a chronic inflammation of the lung airways that can cause coughing, chest tightness, wheezing and/or shortness or breath, according to the American College of Allergy, Asthma & Immunology.

About 80 percent to 90 percent of those with asthma will have exercise as a trigger — but symptoms can also be triggered by allergies (pollen, dust mites, mold, feathers, animal dander, foods), smoke, dirt, gases, odors, colds, flu, bronchitis and other illnesses, stress, cold dry air or hot humid air.

Decades ago, asthmatic kids may have watched from the sidelines instead of participating in sports. These days, medication can control asthma, and nearly all asthmatic kids should be able to participate fully in exercise and sports, said Dr. John Winder, chairman of the American College of Allergy, Asthma & Immunology's nationwide asthma screening program and a physician in Sylvania, Ohio.

"In 32 years of practice, I've never said, 'No, you can't do that,'" said Winder. "The biggest thing is education so kids and parents know what's going on and how to treat it."

Tayte Heller, 14, plays defensive line on his school's football team in Whitehouse, Ohio, and was diagnosed with asthma at age 5 after suffering from severe coughing fits.

A sports fanatic, Heller's also played Little League baseball and soccer. With proper management, he rarely feels asthma's effects on the field. Heller controls his symptoms with a maintenance inhaler used each morning and evening, and a rescue inhaler (for quick relief from symptoms) that he uses just before exercise and for symptoms during practice or games.

"I don't feel different than anyone else," he said. "Sometimes asthma can get in the way when it's really hot and humid, but I just keep an inhaler in my gym shorts and use it while I'm waiting in line to do drills."

"Bronchodilators are very effective at bringing people out of an episode, but they're even better at preventing asthma symptoms from coming on," Winder said. These days, says Winder, more kids are allowed to use inhalers on their own, thanks to better asthma awareness. "Any kid who can be taught how to use an inhaler should be allowed to keep it on him. In grades lower than fourth, we recommend that the classroom teacher hold on to an inhaler in the classroom so it's immediately accessible. For teams, we give them to the coach so the inhaler's on the sideline."

"Some people think that asthma limits you," says Heller's mom, Lynn. "But having doctors who know what they're doing and who get you on the right meds makes a huge difference."

While swimming's one of the more popular sports for asthmatic kids — the warm, humid air is less likely to irritate airways, although chlorine can be an irritant — Dr. Margot Putukian, director of athletic medicine and head team physician at Princeton University, sees college athletes in a variety of sports.

Control and proper diagnosis are the keys. "If someone's using their inhaler often, then their asthma's not well-controlled," she says. "You need to make sure you have the right diagnosis because you might not have asthma."

Other causes of asthma-like symptoms can be allergies, infection, vocal cord dysfunction or even a cardiac condition (more common in older individuals).

"We make sure our athletes monitor their symptoms and that they're responding to the medications," Putukian says.

It's recommended that kids and adults with asthma exercise on a regular basis to improve overall fitness, says Dr. Lynn Millar, an exercise physiologist and fellow of the American College of Sports Medicine.

"Better cardiovascular fitness is related to having less problems with airways, and often kids who exercise regularly know the signs and symptoms of asthma and regulate their medication better," Millar said.

In addition, obesity is a risk factor for asthma.

"The better shape you're in, the more effort is required to bring on an asthma attack," said Putukian. "If you're not fit, it doesn't take much."